Hydrocarbon purification

Abstract

Embodiments of the present disclosure generally relate to methods and systems for purifying hydrocarbons, such as feedstock hydrocarbons containing one or more contaminants. In one or more embodiments, a method of purifying a hydrocarbon is provided and includes flowing a feedstock hydrocarbon stream through a heating unit, then combining the hydrocarbon stream and a primary solvent in a laminar flow reactor to produce a hydrocarbon-solvent stream, flowing the hydrocarbon-solvent stream through a cooling unit, and introducing the hydrocarbon-solvent stream into a separation unit to produce a scrubbed hydrocarbon stream and a solvent stream. The scrubbed hydrocarbon stream has a final contaminant concentration which is less than the initial contaminant concentration. The methods and systems for purifying hydrocarbons may be used to prepare a purified hydrocarbon product having the contaminant reduced by 10 times, about 40 times, about 100 times, or greater compared to the feedstock hydrocarbons.

What is claimed is: 
     
         1 . A method of purifying a hydrocarbon, comprising:
 flowing a feedstock hydrocarbon stream through a heating unit to produce a heated hydrocarbon stream, wherein the feedstock hydrocarbon stream has an initial concentration of a contaminant and comprises one or more of an oil, a fat, a grease, or any combination thereof;   combining the heated hydrocarbon stream and a primary solvent in a laminar flow reactor to produce a hydrocarbon-solvent stream;   flowing the hydrocarbon-solvent stream through a cooling unit to produce a cooled hydrocarbon-solvent stream; and   introducing the cooled hydrocarbon-solvent stream into a separation unit to produce a scrubbed hydrocarbon stream and a solvent stream, wherein the scrubbed hydrocarbon stream has a final concentration of the contaminant, and wherein the final concentration of the contaminant is less than the initial concentration of the contaminant.   
     
     
         2 . The method of  claim 1 , wherein the primary solvent comprises water, steam, or a combination thereof. 
     
     
         3 . The method of  claim 1 , wherein the feedstock hydrocarbon stream comprises soybean oil, corn oil, canola oil, camelina oil, yellow grease, choice white grease, beef tallow, poultry fat, used cooking oil, tall oil, pyrolysis oil, or any combination thereof. 
     
     
         4 . The method of  claim 1 , wherein the feedstock hydrocarbon stream further comprises a polymeric material, a plastic material, or any combination thereof. 
     
     
         5 . The method of  claim 1 , wherein the contaminant comprises one or more of a halide, phosphorous, sulfur, nitrogen, a gum or lecithin, an alkali metal, a metalloid, a heavy metal, or any combination thereof. 
     
     
         6 . The method of  claim 1 , prior to flowing the feedstock hydrocarbon stream through the heating unit, further comprising flowing the feedstock hydrocarbon stream through a deaerator to degas the feedstock hydrocarbon stream. 
     
     
         7 . The method of  claim 1 , further comprising combining an additive into the feedstock hydrocarbon stream, the heated hydrocarbon stream, or both the feedstock hydrocarbon stream and the heated hydrocarbon stream, wherein the additive comprises a hydrolyzing agent, an acid, a base, a salt, a chelating agent, a polar solvent, a non-polar solvent, or any combination thereof. 
     
     
         8 . The method of  claim 7 , wherein the additive comprises one or more of acetic acid, ascorbic acid, citric acid, hydrochloric acid, fumaric acid, glucaric acid, gluconic acid, glutamic acid, hydrochloric acid, lactic acid, malic acid, oxalic acid, phosphoric acid, propionic acid, sulfuric acid, tartaric acid, salts thereof, or any combination thereof. 
     
     
         9 . The method of  claim 1 , further comprising introducing and combining the heated hydrocarbon stream, an additive, and the primary solvent in the laminar flow reactor to produce the hydrocarbon-solvent stream. 
     
     
         10 . The method of  claim 1 , wherein the heated hydrocarbon stream is flowed into a primary solvent pocket within an upper portion of the laminar flow reactor, and wherein the primary solvent pocket comprises the primary solvent. 
     
     
         11 . The method of  claim 1 , wherein the primary solvent is combined with the heated hydrocarbon stream prior to being introduced into the laminar flow reactor. 
     
     
         12 . The method of  claim 1 , wherein the primary solvent comprises steam, wherein a first source of the steam is combined with the heated hydrocarbon stream prior to being introduced into the laminar flow reactor, a combination of the first source of the steam and the heated hydrocarbon stream is flowed into a steam pocket within an upper portion of the laminar flow reactor, and wherein the steam pocket comprises a second source of the steam. 
     
     
         13 . The method of  claim 1 , wherein the laminar flow reactor is a liquid-filled laminar flow reactor comprising an inflow distributor assembly, an outflow header assembly, a packing assembly, or any combination thereof. 
     
     
         14 . The method of  claim 1 , wherein the laminar flow reactor is a vapor-infused laminar flow reactor comprising an inflow distributor assembly, a packing assembly, or any combination thereof. 
     
     
         15 . The method of  claim 1 , further comprising flowing the cooled hydrocarbon-solvent stream through a pressure reduction device, wherein the cooled hydrocarbon-solvent stream is at a first pressure entering the pressure reduction device and at a second pressure exiting the pressure reduction device, and wherein the first pressure is in a range from about 500 psi to about 1,500 psi, and the second pressure is in a range from about 1 psi to about 500 psi, and wherein the second pressure is at least one half of the value of the first pressure. 
     
     
         16 . The method of  claim 1 , wherein the separation unit comprises an extraction column, a vertical extraction column, a horizontal extraction column, a centrifuge, a cross-flow filtration unit, a coalescer, a decanter, an electrostatic separator, a membrane purifier, or any combination thereof. 
     
     
         17 . The method of  claim 1 , wherein the separation unit comprises a vertical extraction column. 
     
     
         18 . The method of  claim 17 , further comprising:
 introducing the cooled hydrocarbon-solvent stream into a lower portion of the vertical extraction column;   introducing a solvent or water stream into an upper portion of the vertical extraction column;   performing a countercurrent liquid-liquid extraction by flowing the cooled hydrocarbon-solvent stream toward the upper portion of the vertical extraction column and flowing the solvent or water stream toward the lower portion of the vertical extraction column; and   flowing the scrubbed hydrocarbon stream from the upper portion of the vertical extraction column, and flowing the solvent stream from the lower portion of the vertical extraction column.   
     
     
         19 . The method of  claim 17 , wherein the vertical extraction column comprises a packing assembly. 
     
     
         20 . The method of  claim 1 , wherein producing the hydrocarbon-solvent stream further comprises:
 introducing a flow of the heated hydrocarbon stream into a headspace in an upper portion of the laminar flow reactor, wherein the flow of the heated hydrocarbon stream is completely or substantially free of turbulence, and wherein the heated hydrocarbon stream is at a first temperature;   introducing a flow of the primary solvent into the headspace in the upper portion of the laminar flow reactor, wherein the flow of the primary solvent is completely or substantially free of turbulence, and wherein the primary solvent is at a second temperature greater than the first temperature; and   condensing the primary solvent into the heated hydrocarbon stream to produce an intermediate stream; and   flowing the intermediate stream through a reaction zone disposed in a lower portion of the laminar flow reactor to produce the hydrocarbon-solvent stream.   
     
     
         21 . The method of  claim 20 , wherein each of a liquid phase within the headspace of the laminar flow reactor and/or the intermediate stream and/or the hydrocarbon-solvent stream independently has a Reynolds number in a range from about 0 to 2,300. 
     
     
         22 . The method of  claim 1 , further comprising flowing the scrubbed hydrocarbon stream through a first finishing unit to produce a purified hydrocarbon stream, wherein the purified hydrocarbon stream has the final concentration of the contaminant or a further reduced concentration of the contaminant. 
     
     
         23 . The method of  claim 1 , wherein the initial concentration of the contaminant is about 40 times or greater than the final concentration of the contaminant. 
     
     
         24 . The method of  claim 1 , wherein the contaminant comprises phosphorus, the initial concentration of the phosphorous is 100 ppm or greater, and the final concentration of the phosphorus is less than 5 ppm, and/or wherein the contaminant comprises total metals, the initial concentration of the total metals is 40 ppm or greater, and the final concentration of the total metals is less than 5 ppm. 
     
     
         25 . The method of  claim 1 , wherein the solvent stream is an aqueous stream, and wherein the aqueous stream is concentrated and/or dried and then blended with a product in a mixer, and wherein the product comprises a processed grain, vegetable meal, fruit meal, protein meal, meat, stover, hay, forage, or any combination thereof. 
     
     
         26 . The method of  claim 1 , further comprising flowing the solvent stream from the separation unit through a second finishing unit to produce a secondary hydrocarbon stream and a secondary solvent stream, wherein each of the solvent stream and the secondary solvent stream independently comprises water. 
     
     
         27 . The method of  claim 26 , wherein the secondary hydrocarbon stream is combined into the feedstock hydrocarbon stream, the feedstock hydrocarbon stream, or a combination thereof. 
     
     
         28 . The method of  claim 26 , wherein the secondary solvent stream is flowed to a water purification system, the laminar flow reactor, the separation unit, or a combination thereof. 
     
     
         29 . The method of  claim 26 , wherein the secondary solvent stream is an aqueous stream, and wherein the aqueous stream is concentrated and/or dried and then blended with a product in a mixer, and wherein the product comprises a processed grain, vegetable meal, fruit meal, protein meal, meat, stover, hay, forage, or any combination thereof. 
     
     
         30 . A method of purifying a hydrocarbon, comprising:
 flowing a feedstock hydrocarbon stream through a deaerator to degas the feedstock hydrocarbon stream, wherein the feedstock hydrocarbon stream has an initial concentration of a contaminant and comprises soybean oil, corn oil, canola oil, camelina oil, yellow grease, choice white grease, beef tallow, poultry fat, used cooking oil, tall oil, pyrolysis oil, or any combination thereof;   flowing the degassed feedstock hydrocarbon stream through a heating unit to produce a heated hydrocarbon stream;   combining the heated hydrocarbon stream and steam in a laminar flow reactor to produce an aqueous hydrocarbon stream;   flowing the aqueous hydrocarbon stream through a cooling unit to produce a cooled aqueous hydrocarbon stream;   introducing the cooled aqueous hydrocarbon stream into a vertical extraction column to produce a scrubbed hydrocarbon stream and an aqueous stream by a countercurrent liquid-liquid extraction, wherein the aqueous stream comprises the contaminant; and   flowing the scrubbed hydrocarbon stream through a first finishing unit to produce a purified hydrocarbon stream, wherein the purified hydrocarbon stream has a final concentration of the contaminant, and wherein the initial concentration of the contaminant is about 40 times or greater than the final concentration of the contaminant.   
     
     
         31 . A method of purifying a hydrocarbon, comprising:
 flowing a feedstock hydrocarbon stream through a heating unit to produce a heated hydrocarbon stream, wherein the feedstock hydrocarbon stream has an initial concentration of a contaminant and comprises one or more of an oil, a fat, a grease, or any combination thereof;   combining the heated hydrocarbon stream and a primary solvent in a laminar flow reactor to produce a hydrocarbon-solvent stream, wherein producing the hydrocarbon-solvent stream further comprises:
 introducing a flow of the heated hydrocarbon stream into a headspace in an upper portion of the laminar flow reactor, wherein the flow of the heated hydrocarbon stream is completely or substantially free of turbulence, and wherein the heated hydrocarbon stream is at a first temperature; 
 introducing a flow of the primary solvent into the headspace in the upper portion of the laminar flow reactor, wherein the flow of the primary solvent is completely or substantially free of turbulence, and wherein the primary solvent is at a second temperature greater than the first temperature; and 
 condensing the primary solvent into the heated hydrocarbon stream to produce an intermediate stream; and 
 flowing the intermediate stream through a reaction zone disposed in a lower portion of the laminar flow reactor to produce the hydrocarbon-solvent stream; 
   introducing the hydrocarbon-solvent stream into a separation unit to produce a scrubbed hydrocarbon stream and a solvent stream, wherein the solvent stream comprises the contaminant; and   flowing the scrubbed hydrocarbon stream through a first finishing unit to produce a purified hydrocarbon stream, wherein the purified hydrocarbon stream has a final concentration of the contaminant, and wherein the final concentration of the contaminant is less than the initial concentration of the contaminant.   
     
     
         32 . The method of  claim 31 , wherein the primary solvent comprises water or steam. 
     
     
         33 . The method of  claim 31 , wherein the solvent stream is an aqueous stream, and wherein the aqueous stream is concentrated and/or dried and then blended with a product in a mixer, and wherein the product comprises a processed grain, vegetable meal, fruit meal, protein meal, meat, stover, hay, forage, or any combination thereof. 
     
     
         34 . The method of  claim 31 , wherein the primary solvent is introduced into the headspace through an injection device, and wherein the primary solvent has a pressure drop across the injection device in a range from about 0.0001 psi to about 40 psi. 
     
     
         35 . The method of  claim 31 , wherein the laminar flow reactor is maintained at a pressure in a range from about 1 psi to about 50 psi of a saturation pressure of the primary solvent at a target reaction temperature. 
     
     
         36 . The method of  claim 31 , wherein each of a liquid phase within the headspace of the laminar flow reactor and/or the intermediate stream and/or the hydrocarbon-solvent stream independently has a Reynolds number in a range from about 0 to 2,300. 
     
     
         37 . A system for purifying a hydrocarbon, comprising:
 a deaerator fluidly coupled to and downstream of a feedstock hydrocarbon source, wherein the feedstock hydrocarbon source is configured to contain a feedstock hydrocarbon having an initial concentration of a contaminant and comprising one or more of an oil, a fat, a grease, or any combination thereof;   a heating portion of a recuperator fluidly coupled to and downstream of the deaerator;   an additive source fluidly coupled to and downstream of the deaerator, wherein the additive source is configured to contain an additive comprising a hydrolyzing agent, an acid, a base, a salt, a chelating agent, a polar solvent, a non-polar solvent, or any combination thereof;   a laminar flow reactor comprising an upper portion opposite a lower portion, and wherein the upper portion of the laminar flow reactor is fluidly coupled to and downstream of the heating portion of the recuperator;   a primary solvent source fluidly coupled to and upstream of the upper portion of the laminar flow reactor;   a cooling portion of the recuperator fluidly coupled to and downstream of the lower portion of the laminar flow reactor;   a pressure reduction device fluidly coupled to and downstream of the cooling portion of the recuperator;   a separation unit fluidly coupled to and downstream of the pressure reduction device, wherein the separation unit comprises a scrubbed hydrocarbon stream outlet and a solvent stream outlet;   a first finishing unit fluidly coupled to and downstream of the scrubbed hydrocarbon stream outlet, wherein the first finishing unit comprises a centrifuge, a cross-flow filtration unit, a coalescer, a decanter, an electrostatic separator, a membrane purifier, or any combination thereof, and wherein the first finishing unit comprises a purified hydrocarbon stream outlet configured to provide a purified hydrocarbon having a final concentration of the contaminant of at least 10 times less than the initial concentration of the contaminant; and   a second finishing unit fluidly coupled to and downstream of the solvent stream outlet, wherein the second finishing unit comprises a centrifuge, a cross-flow filtration unit, a coalescer, a decanter, an electrostatic separator, a membrane purifier, or any combination thereof.